4 HELIX-PAPUINA. 



The species are illustrated on plates 1 to 17. 



No exact diagnosis can be framed for a group in which such 

 diverse forms occur as in Papnina. It is still, however, an easy 

 matter to recognize a species as belonging here ; for with all its 

 variety, the group is a very natural one, well differentiated from 

 other branches of the Helix stock. The central point for the sub- 

 genus, geographically, is New Guinea ; the species extending eastward 

 to the Louisiade, Admiralty and Solomon Islands, with a few in the 

 New Hebrides, and northwestward into the Moluccas. The distribu- 

 tion is, therefore, practically the same as that of the subgenus 

 Chloritis (-{- Planispira, etc.) 



In a previous volume the writer has separated the South American 

 group Oxyckona from Papuina. It remains to sunder the species of 

 southeastern Asia and the zoologically dependent islands, w 7 hich will 

 be discussed after the true Papuina-species. The latter form a 

 moderately homogeneous group, in which it is practically impossible 

 to establish " sections " to correspond to the various names given in 

 the above synonymy. It seems to me a better plan to form the 

 species into a number of groups, each typified by its more prominent 

 specific type. These groups are of somewhat unequal value, and 

 bear various degrees of affinity to each other ; but they undoubtedly 

 form a basis for a natural system. It is likely that anatomical char- 

 acters will afford a good clue to the minor groups. 



I. True PAPUINA ; including species of the Moluccas, New Guinea, 

 Australia, Admiralty, Solomon, Louisiade Is., etc. 



(1.) GROUP OF H. BOIVINI. 



Imperforate, turbinate, the periphery rounded or bluntly angled ; 

 upper lip not expanded or but narrowly expanded ; banded. Sur- 

 face smooth, lightly obliquely striatulate, sometimes having faint spiral 

 lines, but no forward-descending wrinkles. 



H. CONGRUA Pfeiffer. PI. 9, fig. 72. 



Imperforate, trochiform, rather solid, striatulate, flesh-colored, 

 variou.-ly painted with brown bands; spire subcon cave-conic, apex 

 ii little obtuse. Whorls 6, a little convex, the last irregularly 

 in Hated, slightly descending, distinctly rib-striated ; base nearly fiat, 

 more shinin.L:. Aperture oblique, subtetragonal-oval ; peristome 

 blackish-chestnut, expanded, encircled by a streak outside, margins 



